Good question, but that is life with Windows. While you can create a login with ADMIN rights,
it is NOT the same as the default ADMINISTRATOR login.
In addition, all logins with Admin Rights are in the Administrators Group.
If you right-click a shortcut or any *.exe-->run as administrator, you will be presented with a choice of all IDs in the Admin Group.
Technically, there are Parent-ID, Effective-ID, and Current-IDs for processes and using run-as sets Effective-ID to an Admin-id but allows the Parent-ID to be that used to really login. It is my belief that Parent-ID <> Effective-id is how the two are differentiated.